This is a vintage c. 1960's stainless steel Heuer Carrera 2447SN. It has the original stainless steel Gay Freres bracelet with a Heuer stamp and a deployment clasp, and an acrylic crystal. It has the original Heuer winding crown, "pump" style round chronograph push buttons, and a snap down solid case back inside of which is stamped "LEONIDAS SA – SWISS – STAINLESS STEEL." THE 35mm diameter solid three-body case, straight lugs, bracelet, and thin rounded bezel, are polished/brushed. It includes the original silver dial with applied faceted baton hour markers with luminous dots, around a recessed perimeter minute/one-fifth second scale. It has the original steel baton hands with luminous inserts, and a steel center sweep chronograph seconds hand. There are three recessed black subsidiary dials with white Arabic numerals, markers, and hands, including a running small seconds register at 9 o'clock, a 12-hour chronograph totalizer at 6 o'clock, and there is a 30-minute totalizer at 3 o'clock. It has a 48-hour power reserve at full wind, and the 12.4mm thick case, dial, and movement are all signed.